This quiz works best with JavaScript enabled. Home > Cbse > Class 12 > Science > Chemistry Part I > Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics – Quiz 2 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 2 (60 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. The heat of reaction for an endothermic reaction will always be A) Greater than zero. B) Zero. C) Unpredictable. D) Less than zero. Show Answer Correct Answer: A) Greater than zero. 2. Which of the rate law refer to the unit of the rate constant, K is M$^{-2}$s$^{-1}$. A) Rate = K [ A ]$^{2}$ [ B ]$^{2}$. B) Rate = K [ A ]$^{2}$. C) Rate = K [ A ] [ B ]$^{2}$. D) Rate = K [ A ] [ B ]. Show Answer Correct Answer: C) Rate = K [ A ] [ B ]$^{2}$. 3. For a reaction R$\rightarrow$P, half life is observed to be independent of the initial concentration of reactants. What is the order of reaction. A) 3. B) 0. C) 2. D) 1. Show Answer Correct Answer: D) 1. 4. For the reaction A$\rightarrow$ B, the rate of the reaction becomes three times when the concentration of A is increased by nine times .What is the order of the reaction? A) 2. B) 1. C) 0.5. D) 3. Show Answer Correct Answer: C) 0.5. 5. Unit of Rate of reaction? A) Mole/L/s2. B) Mole L-1 s-1. C) Mole/L. D) Mole/kg. Show Answer Correct Answer: B) Mole L-1 s-1. 6. If you shrink the container size that your gas substance is in what will happen? A) The reaction rate will stay the same. B) The reaction rate will speed up. C) The reaction rate will slow down. D) None of the above. Show Answer Correct Answer: B) The reaction rate will speed up. 7. What is a rate law and how is it determined? A) A rate law describes the physical state of reactants. B) A rate law is a measure of temperature in a reaction. C) A rate law is determined solely by theoretical calculations. D) A rate law is an equation that relates the rate of a reaction to the concentration of reactants, determined through experimental data. Show Answer Correct Answer: D) A rate law is an equation that relates the rate of a reaction to the concentration of reactants, determined through experimental data. 8. What is the relationship between concentration and reaction rate? A) Increasing the concentration of reactants typically increases the reaction rate. B) Decreasing the concentration of reactants typically increases the reaction rate. C) Concentration has no effect on reaction rate. D) Increasing the concentration of products typically increases the reaction rate. Show Answer Correct Answer: A) Increasing the concentration of reactants typically increases the reaction rate. 9. Rate laws are typically based on which kind of reactions? A) Physical Reactions. B) Forward Reactions. C) Chemical Reactions. D) Reverse Reactions. Show Answer Correct Answer: B) Forward Reactions. 10. Rate law of an elementary step is based on its A) Reactant. B) Product. C) Molecularity. D) None. Show Answer Correct Answer: C) Molecularity. 11. Molecularity of a reaction is ..... A) No. Of products. B) No. Of order of reaction. C) No. Of reacting species. D) None of above. Show Answer Correct Answer: C) No. Of reacting species. 12. How does the presence of catalyst increase reaction rate? A) It increases collision of particles. B) It increases activation energy. C) It increases the energy of the reactant. D) It lowers down activation energy. Show Answer Correct Answer: D) It lowers down activation energy. 13. What type of reaction is this? A) Third order. B) Second order. C) Unimolecular. D) Pseudo-unimolecular. Show Answer Correct Answer: D) Pseudo-unimolecular. 14. What will be the fraction of molecules having energy equal to or greater than activation energy, Ea? A) K. B) A. C) Ae-Ea/Rt. D) E-Ea/Rt. Show Answer Correct Answer: D) E-Ea/Rt. 15. In any first order reaction, as the reaction proceeds at constant temperature, which describes the corresponding effects on k (the rate constant) and rate? A) K remains the same; rate decreases. B) K and rate both remain the same. C) K remains the same; rate increases. D) K decreases; rate remains the same. Show Answer Correct Answer: A) K remains the same; rate decreases. 16. Reaction rates can change with A) Temperature. B) The addition of catalyst. C) Reactant concentration. D) All of these above. Show Answer Correct Answer: D) All of these above. 17. Rate of the reaction is usually doubled or tripled as the temperature is A) Increased. B) Decreased. C) Both. D) None. Show Answer Correct Answer: A) Increased. 18. The rate of a reaction is doubled when the concentration of reactant A is doubled. What is the order of the reaction with respect to A? A) Second order. B) Third order. C) Zero order. D) First order. Show Answer Correct Answer: D) First order. 19. In terms of collision theory, a reaction occurs when the molecules collide with sufficient energy to break the bonds already in place. What is this energy called? A) Activity series. B) Concentration gradient. C) Reaction mechanism. D) Activation energy. Show Answer Correct Answer: D) Activation energy. 20. In general, an increase in temperature of 10$^\circ$C will have what effect on reaction rate:A. Double the rate B. Half the rate C. Triple the rate D. Increase the rate but not by a specific amount A) A. B) B. C) C. D) D. Show Answer Correct Answer: A) A. 21. For an elementary reaction 2A + B $\rightarrow$C + D, the molecularity is A) One. B) Zero. C) Three. D) Two. Show Answer Correct Answer: C) Three. 22. In powdered state rate of the reaction is maximum is due to A) Decrease in surface area. B) Increase in density. C) Decrease in density. D) Increase in surface area. Show Answer Correct Answer: D) Increase in surface area. 23. Which of the following are true of reaction rates?I. The overall rate law is determined by the fastest step of a reactionII. The presence of a catalyst will increase the number of molecules entering the transition stateIII. An increase in temperature will increase the rate of a reactionIV. Decreasing the concentration of reactants will increase the rate at which products yield A) I+IV. B) I+II+III. C) II + III. D) II+III+IV. Show Answer Correct Answer: C) II + III. 24. Which of the following could be used to follow the rate of a reaction?I. Change in temperature as the reaction proceedsII. Change in colour as the reaction proceedsIII. Change in electrical conductivity as the reaction proceeds A) I and II only. B) I and IIl only. C) Il and IIl only. D) I, ll and IIl only. Show Answer Correct Answer: D) I, ll and IIl only. 25. How does the orientation of molecules affect collisions? A) Molecular orientation influences the effectiveness of collisions and the likelihood of reactions. B) Molecular orientation has no impact on reaction rates. C) Collisions are only affected by temperature, not orientation. D) Molecules collide randomly regardless of their orientation. Show Answer Correct Answer: A) Molecular orientation influences the effectiveness of collisions and the likelihood of reactions. 26. What is the relationship between rate of reaction and concentration of reactants? A) Jointly proportional. B) Inversely proportional. C) Directly proportional. D) No relationship. Show Answer Correct Answer: C) Directly proportional. 27. Units of second order rate constant = ..... A) L$^{2}$ mol$^{-2}$ time$^{-1}$. B) Time$^{-1}$. C) L mol$^{-1}$ time$^{-1}$. D) Mol L$^{-1}$ time$^{-1}$. Show Answer Correct Answer: C) L mol$^{-1}$ time$^{-1}$. 28. A thermodynamically favorable reaction proceeds spontaneously. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: B) False. 29. How does temperature influence the activation energy of a reaction? A) Temperature increases the rate of reaction by providing more molecules with energy to overcome the activation energy barrier. B) Higher temperatures increase the activation energy required for a reaction. C) Temperature decreases the rate of reaction by lowering the energy of molecules. D) Temperature has no effect on the activation energy of a reaction. Show Answer Correct Answer: A) Temperature increases the rate of reaction by providing more molecules with energy to overcome the activation energy barrier. 30. Catalysts permit reactions to happen with a ..... activiation energy. A) Lower. B) Higher. C) All the above. D) None of the above. Show Answer Correct Answer: A) Lower. 31. What is explaining behaviors of a system at equilibrium? A) Avagadro's Law. B) Le Chatelier Principle. C) Collusion Theory. D) Boyles Law. Show Answer Correct Answer: B) Le Chatelier Principle. 32. Units of rate is ..... A) M/s. B) M.s. C) Mol/s. D) S/M. Show Answer Correct Answer: A) M/s. 33. Determine order of reaction for the reactant A and B based on this rate law:Rate = K [A]$^{2}$[B]$^{1}$ A) First order and [B] first order. B) First order and [B] second order. C) Second order and [B] first order. D) Second order and [B] second order. Show Answer Correct Answer: C) Second order and [B] first order. 34. How does a catalyst influence the rate of a reaction? A) A catalyst increases the rate of a reaction by lowering the activation energy. B) A catalyst changes the products of the reaction. C) A catalyst decreases the rate of a reaction by increasing the activation energy. D) A catalyst has no effect on the rate of a reaction. Show Answer Correct Answer: A) A catalyst increases the rate of a reaction by lowering the activation energy. 35. Half life period for a zero order reaction is directly proportional to the initial concentration of the reactant. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 36. If we dissolve less solute than the amount needed to form a saturated solution, the solution is unsaturated. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 37. When you double the concentration of this reactant the rate of the reaction doesn't change. It is ..... order A) First. B) Second. C) Zero. D) None of the above. Show Answer Correct Answer: C) Zero. 38. When the temperature increases, the rate of reaction: A) Increases. B) Is unpredictable. C) Decreases. D) Remains constant. Show Answer Correct Answer: A) Increases. 39. Describe how inhibitors affect reaction rates. A) Inhibitors increase reaction rates by enhancing enzyme activity. B) Inhibitors have no effect on reaction rates whatsoever. C) Inhibitors only affect the temperature of the reaction. D) Inhibitors decrease reaction rates by preventing enzyme-substrate interactions. Show Answer Correct Answer: D) Inhibitors decrease reaction rates by preventing enzyme-substrate interactions. 40. Suppose the activation energy of a certain reaction is 250 kJ/mol. If the rate constant at T$_{1}$ = 300 K is k$_{1}$ and the rate constant at T$_{2}$ = 320 K is k$_{2}$, then the reaction is ..... times faster at 320 K than at 300 K. (Hint:Solve for k$_{2}$/k$_{1}$.) A) 3 x 10$^{-29}$. B) 525. C) 0.067. D) 15.0. Show Answer Correct Answer: B) 525. 41. The rate of reaction for the decomposition of hydrogen peroxide decreases with time because A) Temperature of hydrogen peroxide decreases. B) Product of reaction decreases. C) Volume of hydrogen peroxide decreases. D) Concentration of hydrogen peroxide decreases. Show Answer Correct Answer: D) Concentration of hydrogen peroxide decreases. 42. What is the Arrhenius equation and what does it represent? A) The Arrhenius equation is used to determine the pH of a solution. B) The Arrhenius equation relates the rate of a chemical reaction to temperature and activation energy. C) The Arrhenius equation calculates the pressure of a gas. D) The Arrhenius equation describes the relationship between concentration and volume. Show Answer Correct Answer: B) The Arrhenius equation relates the rate of a chemical reaction to temperature and activation energy. 43. The amount of solute needed to form a saturated solution in a given quantity of solvent is known as the solubility of that solvent. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: B) False. 44. What is the unit of rate for a reaction involving concentration in mol L-1? A) Mol L-1 s-1. B) Mol L-1. C) L mol-1 s-1. D) S-1. Show Answer Correct Answer: A) Mol L-1 s-1. 45. Under the collision theory, the particles must collide with ..... and ..... for a reaction to occur. A) Sufficient rate and sufficient energy. B) Sufficient surface area and correct orientation. C) Sufficient catalyst and sufficient energy. D) Sufficent energy and correct orientation. Show Answer Correct Answer: D) Sufficent energy and correct orientation. 46. Radioactive decay follows A) 2nd order. B) 1st order. C) 3rd order. D) 0 order. Show Answer Correct Answer: B) 1st order. 47. How do concentration changes affect reaction rates? A) Higher concentration decreases reaction rates due to fewer collisions. B) Lower concentration increases reaction rates by slowing down collisions. C) Concentration changes have no effect on reaction rates. D) Higher concentration increases reaction rates due to more frequent collisions. Show Answer Correct Answer: D) Higher concentration increases reaction rates due to more frequent collisions. 48. Rate of the reaction is usually doubled or tripled as temperature is increased due to increase in A) Ineffective collision. B) External energy. C) Effective collision. D) Internal energy. Show Answer Correct Answer: C) Effective collision. 49. Rate Constant unit of first order reaction A) Per second. B) Second. C) Mol/sec. D) L/mol/sec. Show Answer Correct Answer: A) Per second. 50. The half-life of a first-order reaction is 10 minutes. How much time is required for the reactant concentration to decrease to 25% of its initial value? A) 40 minutes. B) 20 minutes. C) 30 minutes. D) 10 minutes. Show Answer Correct Answer: B) 20 minutes. 51. For a zero-order reaction, half-life is given by: A) T$_{1/2}$= $\frac{0.693}{K}$. B) T$_{1/2}$= $\frac{\left[A\right]_0}{2K}$. C) T$_{1/2}$= $\frac{1}{K\left[A\right]_0}$. D) T$_{1/2}$= $K\left[A\right]_0$. Show Answer Correct Answer: B) T$_{1/2}$= $\frac{\left[A\right]_0}{2K}$. 52. For a second-order reaction, if 1/[A] vs. t has a slope of 0.02 L/mol/s, the rate constant is: A) 0.01 L/mol/s. B) 0.05 L/mol/s. C) 0.02 L/mol/s. D) 0.04 L/mol/s. Show Answer Correct Answer: C) 0.02 L/mol/s. 53. What is the theory which explains how chemical reaction occurs? A) Diffusion. B) Emulsion. C) Collision. D) Big Bang. Show Answer Correct Answer: C) Collision. 54. The rate constant of a reaction depends upon A) Initial concentration of the reactants. B) Extent of the reaction. C) Temperature of the reaction. D) The time of completion of reaction. Show Answer Correct Answer: D) The time of completion of reaction. 55. In a reaction where the rate is determined by the concentration of a single reactant, what is the order of the reaction? A) Third order. B) Second order. C) Zero order. D) First order. Show Answer Correct Answer: D) First order. 56. What is the unit for first order degradation rate constant? A) Time/concentration. B) Concentration time. C) Time. D) Reciprocal of time. Show Answer Correct Answer: D) Reciprocal of time. 57. A catalyst increases the rate of a reaction by: A) Increasing activation energy. B) Increasing the energy of reactants. C) Providing an alternative pathway with lower activation energy. D) Increasing temperature. Show Answer Correct Answer: C) Providing an alternative pathway with lower activation energy. 58. The theory that says in order for a reaction to occur, reactants must have sufficient energy and collide in a correct orientation. A) Collision Theory. B) Activation Energy Theory. C) Dalton's Theory. D) Activated Complex Theory. Show Answer Correct Answer: A) Collision Theory. 59. For a drug degrading by zero order kinetics, concentration of the drug decreases with time in an exponential trend. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: B) False. 60. What is Integrated rate equation for First order reaction? A) Log r$_{0 }$-log r = kt/ 2.303. B) R$_{0 }$-R = kt. C) Both a and b. D) None of the above. Show Answer Correct Answer: A) Log r$_{0 }$-log r = kt/ 2.303. ← PreviousNext →Related QuizzesScience QuizzesClass 12 QuizzesClass 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 1Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 3Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 4Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 5Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 6Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 7Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 8Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 9 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books